How to Decode/Convert a Base64 String to Nsdata

How to convert Base64 string to NSData?

To convert from Base64 string to NSData

 let nsd: NSData = NSData(base64EncodedString: Image, options: NSDataBase64DecodingOptions.IgnoreUnknownCharacters)!

To Convert to Blob

nsd.datatypeValue

How to decode / convert a base64 string to NSData?

This is what I was looking for.

+ (NSData *)base64DataFromString: (NSString *)string
{
unsigned long ixtext, lentext;
unsigned char ch, inbuf[4], outbuf[3];
short i, ixinbuf;
Boolean flignore, flendtext = false;
const unsigned char *tempcstring;
NSMutableData *theData;

if (string == nil)
{
    return [NSData data];
}

ixtext = 0;

tempcstring = (const unsigned char *)[string UTF8String];

lentext = [string length];

theData = [NSMutableData dataWithCapacity: lentext];

ixinbuf = 0;

while (true)
{
    if (ixtext >= lentext)
    {
        break;
    }

    ch = tempcstring [ixtext++];

    flignore = false;

    if ((ch >= 'A') && (ch <= 'Z'))
    {
        ch = ch - 'A';
    }
    else if ((ch >= 'a') && (ch <= 'z'))
    {
        ch = ch - 'a' + 26;
    }
    else if ((ch >= '0') && (ch <= '9'))
    {
        ch = ch - '0' + 52;
    }
    else if (ch == '+')
    {
        ch = 62;
    }
    else if (ch == '=')
    {
        flendtext = true;
    }
    else if (ch == '/')
    {
        ch = 63;
    }
    else
    {
        flignore = true; 
    }

    if (!flignore)
    {
        short ctcharsinbuf = 3;
        Boolean flbreak = false;

        if (flendtext)
        {
            if (ixinbuf == 0)
            {
                break;
            }

            if ((ixinbuf == 1) || (ixinbuf == 2))
            {
                ctcharsinbuf = 1;
            }
            else
            {
                ctcharsinbuf = 2;
            }

            ixinbuf = 3;

            flbreak = true;
        }

        inbuf [ixinbuf++] = ch;

        if (ixinbuf == 4)
        {
            ixinbuf = 0;

            outbuf[0] = (inbuf[0] << 2) | ((inbuf[1] & 0x30) >> 4);
            outbuf[1] = ((inbuf[1] & 0x0F) << 4) | ((inbuf[2] & 0x3C) >> 2);
            outbuf[2] = ((inbuf[2] & 0x03) << 6) | (inbuf[3] & 0x3F);

            for (i = 0; i < ctcharsinbuf; i++)
            {
                [theData appendBytes: &outbuf[i] length: 1];
            }
        }

        if (flbreak)
        {
            break;
        }
    }
}

return theData;
}

convert base64 decoded NSData to NSString

There is a built in function in NSData

[data base64Encoding];
[data base64EncodedStringWithOptions:NSDataBase64Encoding76CharacterLineLength];

How to convert base64 into NSDATA in swift

This works:

Swift 3 and 4:

var audioData = Data(base64Encoded: recording_base64, options: .ignoreUnknownCharacters)

Swift 2:

var audioData = NSData(base64EncodedString: recording_base64, options: NSDataBase64DecodingOptions.IgnoreUnknownCharacters)

Decode base64 data on iOS

Note: The Base64 decoded output is not a string, it is binary data. You are getting nil returned because it is not a UTF-8 string and arbitrary data is generally not valid UTF-8.

NSString *base64 = @"RwSBFR7iQ5vQYLqZE60hJEyOaU4VVGcqtvnB2A1zQEylNdN9tTZIOfwGMwDbMZlnnvT7lm80L1MkvDNHqivdRAV4Ymtizw3Fd3GWBZ+xFVIAk0H3lQWzAr43G7TRCYfcr5Ijuj0qGIEF1FLpY6tlYNMI0C3J6UXHqnd3vu4XuwIHi1gVciOxuP+iqgjvjM3Oqy8sU0YITC3ywxPASh14azvcPu9F1/KYS1J1JzN3XsTzscHfkdry0hbz5H0l+6UmUz9Sb9HTGxxx9mwFB821I8DfZc2RGx8WmFuaNzgLFhS6CdwFG9yALPk4wBUqIxEAy4w/oLPosQqZ7Z9LJnQ4SA==";
NSLog(@"base64: %@", base64);
NSData *data = [[NSData alloc] initWithBase64EncodedString:base64 options:nil];
NSLog(@"data: %@", data);

Output:

base64: RwSBFR7iQ5vQYLqZE60hJEyOaU4VVGcqtvnB2A1zQEylNdN9tTZIOfwGMwDbMZlnnvT7lm80L1MkvDNHqivdRAV4Ymtizw3Fd3GWBZ+xFVIAk0H3lQWzAr43G7TRCYfcr5Ijuj0qGIEF1FLpY6tlYNMI0C3J6UXHqnd3vu4XuwIHi1gVciOxuP+iqgjvjM3Oqy8sU0YITC3ywxPASh14azvcPu9F1/KYS1J1JzN3XsTzscHfkdry0hbz5H0l+6UmUz9Sb9HTGxxx9mwFB821I8DfZc2RGx8WmFuaNzgLFhS6CdwFG9yALPk4wBUqIxEAy4w/oLPosQqZ7Z9LJnQ4SA==

data: <47048115 1ee2439b d060ba99 13ad2124 4c8e694e 1554672a b6f9c1d8 0d73404c a535d37d b5364839 fc063300 db319967 9ef4fb96 6f342f53 24bc3347 aa2bdd44 0578626b 62cf0dc5 77719605 9fb11552 009341f7 9505b302 be371bb4 d10987dc af9223ba 3d2a1881 05d452e9 63ab6560 d308d02d c9e945c7 aa7777be ee17bb02 078b5815 7223b1b8 ffa2aa08 ef8ccdce ab2f2c53 46084c2d f2c313c0 4a1d786b 3bdc3eef 45d7f298 4b527527 33775ec4 f3b1c1df 91daf2d2 16f3e47d 25fba526 533f526f d1d31b1c 71f66c05 07cdb523 c0df65cd 911b1f16 985b9a37 380b1614 ba09dc05 1bdc802c f938c015 2a231100 cb8c3fa0 b3e8b10a 99ed9f4b 26743848>

Converting between NSData and base64 strings

Scroll down to the Conclusion section on the page you linked and download the provided NSData+Base64 files. Its the best solution I have seen so far and is incredibly easy to use. If you can learn anything about Cocoa, you can learn to use that project.

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Example

NSString *originalString = [NSString stringWithFormat:@"test"]; 
NSData *data = [NSData dataFromBase64String:originalString];  
NSLog([data base64EncodedString]); 

The above will print out the original string after converting it to base64 and back to a normal unencoded string.

Objective-c Base64 NSString to NSData conversion

I believe you issue is that your not sending in a base64 encoded string to initWithBase64EncodedString.

Swift NSData from base64encoded string returns nil

Try to use IgnoreUnknownCharacters option.

Or try to use initWithBase64EncodedString from NSDataAdditions

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